Artem Chigvintsev, who has danced as a pro partner in the last two seasons of Dancing With the Stars, will not return as a pro in the upcoming 21st season. The dancer was surprisingly omitted from the pro lineup announced Wednesday, leaving fans to scratch their heads.

Chigvintsev had been announced as returning back in August and the pro had even been tweeting about the season leading up to Wednesday's announcement. But something changed.

It is unknown what happened in the days leading up to the Wednesday announcement. Perhaps a celebrity dropped out at the last second. Maybe DWTS producers decided that another pro would be a better fit for a celebrity than Chigvintsev. We may never know. But luckily for fans of the pro, he did say he would be back in the ballroom in some capacity.

Fellow pro Peta Murgatroyd will not be competing in the upcoming season either but for a different reason. The fan favorite pro suffered an injury and was told that she needs surgery, forcing her to sit out of the season.

The new season will have the usual lineup up Derek Hough, Mark Ballas, Val Chmerkovskiy, Tony Dovolani and more among pros, but it will also feature the return of three pros from DWTS past. Louis van Amstel, Anna Trebunskaya and Lindsay Arnold are all returning next season after 4-5 season hiatuses.

Dancing With the Stars season 21 premieres Monday, Sept. 14 at 8 p.m. ET/PT on ABC.